A top Hollywood investigator has claimed that Whitney Houston was murdered. According to The National Enquirer, Paul Huebl said that he has evidence -- the singer's killers are caught on tape. He explained, "I have evidence that points to Whitney being a victim of a high powered drug dealers who sent thugs to collect a huge debt she owed for drugs." The PI spoke with a network of drug informants and took another look at the coroner to gather evidence -- which he is turning over the Chicago field office of the FBI.

Huebl said that two unknown men kept showing up at The Beverly Hills Hilton where Whitney was staying and blended in with her entourage. Huebl said that the day before Whitney's death, she received a cocaine delivery but was later heard saying "I'm tired of this sh*t" -- which he claims was Whitney referring to her $1.5 million drug debt. On February 11th -- the day Whitney died, she was left alone in her hotel room for 45 minutes and that's when one or both killers went into her room and were caught on surveillance video.

Huebl also disagrees with the coroner's report that no foul play was involved, saying,"Whitney's body shows classic defense wounds that would have occurred while she was battling for her life." He said that her injuries and evidence points to a struggle in the last minutes of her life in her hotel room.